This free human circulatory system MCQ test is the tenth set in our 72nd BPSC practice series and the first of two biology sets. Its 25 questions come from NCERT Class 11 chapters on body fluids and circulation, excretory products and locomotion: plasma and formed elements, Rh incompatibility, the cardiac cycle, clotting, nephron structure, micturition and the kinds of muscle. Each question shows the correct answer and an explanation as soon as you choose an option, and you can work out your score with BPSC-style negative marking at the end. For more practice, see our free BPSC mock test series.
What this test covers: Plasma composition, WBC types, platelets, erythroblastosis foetalis, lymph, open and closed circulation, the SA node, heart sounds, fibrin and thrombin, vertebrate hearts, pulmonary and systemic circulation, nephridia and Malpighian tubules, the nephron, urine volume, angina, haemodialysis, and skeletal versus smooth muscle.
Blood, Circulation, Excretion & Muscles
25 questions · NCERT Class 11 Biology · BPSC prelims pattern
How this test works
Click the option you think is right. It locks, turns green if correct or red if not, and the explanation opens underneath. Your score updates in the bar at the top as you go, and Calculate final score at the bottom gives the full breakdown. Choose (E) Not attempted when you would only be guessing, exactly as you would bubble E on the BPSC OMR sheet.
+1 mark — Correct answer
−1/3 mark — Wrong answer
0 — no penalty — (E) Not attempted, the fifth bubble on every question
−1/3 mark — Row left completely blank in the real exam
Blood & circulation12 questions
1. Which of the following correctly describes plasma?
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Answer: (B) It constitutes nearly 55% of blood and contains about 90–92% water
Plasma is the straw-coloured fluid that makes up nearly 55 per cent of blood and is about 90 to 92 per cent water, with proteins such as fibrinogen, globulins and albumins.
2. Which combination correctly represents the formed elements of human blood?
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Answer: (B) RBCs, WBCs and platelets
The formed elements are erythrocytes (RBCs), leucocytes (WBCs) and platelets, which together make up about 45 per cent of blood.
3. Which of the following is correctly matched?
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Answer: (B) Eosinophils — resistance to infections and allergic reactions
Eosinophils resist infections and are involved in allergic reactions. Neutrophils and monocytes are phagocytic, while basophils secrete histamine, serotonin and heparin.
4. Platelets are best described as:
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Answer: (B) Cell fragments produced from megakaryocytes
Platelets (thrombocytes) are cell fragments produced from megakaryocytes in the bone marrow and release factors needed for clotting.
5. Erythroblastosis foetalis is associated particularly with:
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Answer: (B) Rh-negative mother and Rh-positive foetus
Erythroblastosis foetalis can occur when an Rh-negative mother carries an Rh-positive foetus and her anti-Rh antibodies attack the baby’s RBCs in a later pregnancy.
6. Which statement best distinguishes tissue fluid from lymph?
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Answer: (B) Tissue fluid is derived from blood and is collected by lymphatic vessels to form lymph
Tissue fluid (interstitial fluid) leaks from the capillaries, and the part that drains into the lymphatic vessels is called lymph.
7. Which organism is correctly associated with a closed circulatory system?
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Answer: (C) Annelid
Annelids and vertebrates have closed circulatory systems. Arthropods and molluscs have open systems in which blood flows through body cavities.
8. Which part of the cardiac conduction system normally generates the highest number of action potentials per minute?
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Answer: (D) SAN
The sino-atrial node (SAN) generates the maximum number of action potentials, about 70 to 75 per minute, and acts as the pacemaker.
9. Assertion (A): The first heart sound is produced when the semilunar valves close.
Reason (R): The first heart sound is associated with closure of the tricuspid and bicuspid valves.
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Answer: (D) A is false, but R is true
The first heart sound (lub) comes from closure of the tricuspid and bicuspid valves; the second (dub) from closure of the semilunar valves. A is false and R is true.
10. Consider the following statements regarding blood coagulation:
- Fibrin is formed from fibrinogen.
- Thrombin converts fibrinogen into fibrin.
- Thrombin itself is directly the inactive precursor of fibrin.
- Calcium ions have an important role in clotting.
Which statements are correct?
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Answer: (C) 1, 2 and 4 only
Thrombin converts fibrinogen to fibrin and calcium ions are needed for clotting, so 1, 2 and 4 are correct. Statement 3 is wrong: thrombin forms from prothrombin, it is not a precursor of fibrin.
11. Consider the following statements about vertebrate hearts:
- Fish possess a two-chambered heart.
- Amphibians possess a three-chambered heart.
- Crocodiles possess a three-chambered heart like other reptiles.
- Birds and mammals possess four-chambered hearts.
Which statements are correct?
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Answer: (A) 1, 2 and 4 only
Fish have two-chambered hearts, amphibians and most reptiles three-chambered, and birds and mammals four-chambered. Crocodiles are the exception with four chambers, so statement 3 is wrong.
12. Consider the following statements regarding circulation in humans:
- Pulmonary circulation begins with deoxygenated blood leaving the right ventricle.
- Pulmonary circulation ends with oxygenated blood entering the left atrium.
- Systemic circulation begins with oxygenated blood leaving the left ventricle.
- Hepatic portal circulation carries blood from the liver to the intestine before systemic circulation.
Which statements are correct?
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Answer: (B) 1, 2 and 3 only
Pulmonary circulation runs from the right ventricle to the lungs and back to the left atrium, and systemic circulation starts at the left ventricle. Statement 4 is wrong: the hepatic portal vein carries blood from the intestine to the liver.
Excretion9 questions
13. Which one of the following pairs is correctly matched with respect to the principal excretory structure?
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Answer: (B) Annelids — Nephridia
Annelids such as the earthworm excrete through nephridia. Flatworms use flame cells, insects Malpighian tubules and crustaceans green (antennal) glands.
14. Which sequence correctly represents the major structural organisation of a nephron?
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Answer: (A) Bowman’s capsule → PCT → Henle’s loop → DCT → collecting duct
A nephron begins with the Bowman’s capsule enclosing the glomerulus, followed by the proximal convoluted tubule, the loop of Henle, the distal convoluted tubule and the collecting duct.
15. Which of the following statements regarding urine is correct?
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Answer: (C) Adult humans excrete approximately 1–1.5 litres of urine per day.
An adult passes about 1 to 1.5 litres of slightly acidic urine a day, containing about 25 to 30 g of urea.
16. Which of the following correctly describes micturition?
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Answer: (B) Release of urine from the urinary bladder through the urethra
Micturition is the release of urine from the urinary bladder through the urethra, triggered by a neural reflex when the bladder fills.
17. A mature mammalian erythrocyte is particularly suited for oxygen transport because it:
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Answer: (B) Is biconcave and contains haemoglobin but lacks a nucleus
Mammalian RBCs are biconcave, lack a nucleus and are packed with haemoglobin, which maximises the space for carrying oxygen.
18. Which valve guards the right atrioventricular opening?
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Answer: (B) Tricuspid valve
The tricuspid valve guards the opening between the right atrium and right ventricle; the bicuspid (mitral) valve is on the left side.
19. Which one of the following is the correct approximate percentage of neutrophils among human WBCs?
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Answer: (D) 60–65%
Neutrophils are the most abundant WBCs at 60 to 65 per cent, followed by lymphocytes (20 to 25 per cent).
20. Which of the following is correctly matched with the disorder?
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Answer: (A) Angina — acute pain caused by insufficient oxygen supply to cardiac muscle
Angina pectoris is chest pain caused by an inadequate oxygen supply to the heart muscle. Hypertension means blood pressure above 140/90, not below 90/60.
21. During haemodialysis, heparin is used primarily as:
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Answer: (B) An anticoagulant
Heparin, an anticoagulant, is added to blood during haemodialysis so that it does not clot as it passes through the dialysing unit.
Muscles4 questions
22. Which of the following correctly represents the three main types of movement exhibited by cells of the human body?
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Answer: (A) Amoeboid, ciliary and muscular
Human cells show amoeboid movement (macrophages, leucocytes), ciliary movement (respiratory tract, oviducts) and muscular movement (limbs, jaws, tongue).
23. Approximately what percentage of an adult human’s body weight is contributed by muscles?
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Answer: (C) 40–50%
Muscles make up 40 to 50 per cent of the body weight of an adult human.
24. Which type of muscle is correctly characterised as striated and voluntary?
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Answer: (C) Skeletal muscle
Skeletal muscles are striated and under voluntary control. Smooth (visceral) muscle is non-striated and involuntary; cardiac muscle is striated but involuntary.
25. The plasma membrane of a muscle fibre is called:
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Answer: (B) Sarcolemma
The sarcolemma is the plasma membrane of a muscle fibre; the sarcoplasm is its cytoplasm and the sarcomere is the contractile unit.
Your result
Automatic scoring needs JavaScript. Until it runs, tally by hand: score = correct − (wrong ÷ 3).
Finished, or stopping here? This counts every question you have answered so far.
Show the full answer key
1 B · 2 B · 3 B · 4 B · 5 B · 6 B · 7 C · 8 D · 9 D · 10 C · 11 A · 12 B · 13 B · 14 A · 15 C · 16 B · 17 B · 18 B · 19 D · 20 A · 21 B · 22 A · 23 C · 24 C · 25 B
Scoring: +1 correct, −1/3 wrong, 0 for (E) Not attempted, −1/3 for a row left blank in the real exam.
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